Technical data
90 Understanding Your Agilent ChemStation
4 Integration
Baseline Allocation
The Start of the Baseline
If no baseline is found at the start of the run, the start of the baseline is 
established in one of the following ways:
• from the start of the run to the first baseline point, if the start of run point 
is lower than the first baseline point,
• from the start of the run to the first valley point, if the start of run point is 
lower than the first valley,
• from the start of the run to the first valley point, if the first valley 
penetrates an imaginary line drawn from the start of run to the first 
baseline,
• from the start of the run to a horizontal baseline extended to the first 
baseline point.
Tick Marks
Tick marks identify the beginning and end of a peak. Their positions are 
determined by the peak start and peak end times, saved in the peak table. 
The End of the Baseline
The last valid baseline point is used to designate the end of the baseline. In 
cases where the run does not end on the baseline, the end of the baseline is 
calculated from the last valid baseline point to the established baseline drift.
If a peak ends in an apparent valley but the following peak is below the area 
reject value as you have set it, the baseline is projected from the beginning of 
the peak to the next true baseline point. If a peak starts in a similar way, the 
same rule applies.










